Effects of autumn harvest date on the performance of white clover/grass mixtures in Nova Scotia

SUMMARY White clover (Trifolium repens L.) is well adapted to the cool moist climate of Atlantic Canada, where it improves digestibility and protein content in pastures, but little is known about its role in pasture stockpiled for autumn grazing in this region. The objectives of this study were to determine the effect of autumn harvest dates on dry matter yield and clover content in herbage mixtures. Two experiments conducted in Nova Scotia between 1985 and 1991 on two different soil types showed that the effects of autumn harvest dates were inconsistent from year to year. Herbage growth rates ranged from 11 to 41 kg/ha per day between early September and mid-October. Clover content was generally lower in August–early September than in November harvests and declined in subsequent years irrespective of harvest date or forage species. Kersey White and Sonja white clovers were the highest yielding cultivars. Crude protein declined in late autumn harvests whereas acid detergent fibre tended to increase, and there were differences between years. Forage quality was significantly better in tall fescue (Festuca arundinacea Schreb.) than orchardgrass (Dactylis glomerata L.)/white clover mixtures.